Background: This article mainly focuses on the causes, the organisms involved and the protocols of disinfection of the water-pipelines of the dental units. Aim: The aim of this article is to review different herbal irrigants used in the field of endodontics. Materials and methods: A literature review is conducted using electronic databases “PubMed”, “Google Scholar” and “Scopus”, using keywords “dental chair contamination”, “Micro-organisms”, “water-pipelines”, “dental water units”, “Biofilms”. Out of 107 articles, only 35 articles were relevant for this study. Conclusion: To conclude from this review DUW contamination is now more clearly defined, changes can be made by dental manufacturers and the scientific community in approaches to prevention and control.